Some fixes to _lookup_image_glance: fix the return value from lookup_image, attach the disk read-only before running pygrub, and add some debug logging.
Some fixes to _lookup_image_glance: fix the return value from lookup_image,
attach the disk read-only before running pygrub, and add some debug logging.

ruslanloman/nova,aristanetworks/arista-ovs-nova,josephsuh/extra-specs,dstroppa/openstack-smartos-nova-grizzly,NoBodyCam/TftpPxeBootBareMetal,sebrandon1/nova,mandeepdhami/nova,gooddata/openstack-nova,Juniper/nova,Tehsmash/nova,watonyweng/nova,cloudbase/nova,alvarolopez/nova,aristanetworks/arista-ovs-nova,sileht/deb-openstack-nova,rahulunair/nova,saleemjaveds/https-github.com-openstack-nova,Triv90/Nova,JianyuWang/nova,iuliat/nova,sileht/deb-openstack-nova,iuliat/nova,virtualopensystems/nova,ted-gould/nova,jianghuaw/nova,blueboxgroup/nova,TieWei/nova,alvarolopez/nova,mgagne/nova,orbitfp7/nova,affo/nova,houshengbo/nova_vmware_compute_driver,akash1808/nova_test_latest,DirectXMan12/nova-hacking,viggates/nova,CEG-FYP-OpenStack/scheduler,imsplitbit/nova,cyx1231st/nova,OpenAcademy-OpenStack/nova-scheduler,usc-isi/extra-specs,blueboxgroup/nova,klmitch/nova,rahulunair/nova,JioCloud/nova,Metaswitch/calico-nova,eharney/nova,scripnichenko/nova,sridevikoushik31/nova,joker946/nova,ewindisch/nova,leilihh/nova,belmiromoreira/nova,projectcalico/calico-nova,Juniper/nova,fajoy/nova,anotherjesse/nova,sileht/deb-openstack-nova,JioCloud/nova_test_latest,maheshp/novatest,Brocade-OpenSource/OpenStack-DNRM-Nova,mandeepdhami/nova,houshengbo/nova_vmware_compute_driver,kimjaejoong/nova,klmitch/nova,bclau/nova,anotherjesse/nova,maoy/zknova,qwefi/nova,sridevikoushik31/openstack,Juniper/nova,BeyondTheClouds/nova,usc-isi/extra-specs,takeshineshiro/nova,cloudbau/nova,cloudbase/nova,dawnpower/nova,klmitch/nova,dstroppa/openstack-smartos-nova-grizzly,tealover/nova,scripnichenko/nova,bgxavier/nova,isyippee/nova,superstack/nova,CloudServer/nova,termie/nova-migration-demo,vmturbo/nova,DirectXMan12/nova-hacking,CiscoSystems/nova,Triv90/Nova,Tehsmash/nova,gspilio/nova,usc-isi/nova,projectcalico/calico-nova,tealover/nova,berrange/nova,vmturbo/nova,termie/pupa,salv-orlando/MyRepo,zaina/nova,vladikr/nova_drafts,SUSE-Cloud/nova,nikesh-mahalka/nova,devendermishrajio/nova_test_latest,maheshp/novatest,Triv90/Nova,tanglei528/nova,bclau/nova,TwinkleChawla/nova,mikalstill/nova,LoHChina/nova,shail2810/nova,Yusuke1987/openstack_template,jianghuaw/nova,psiwczak/openstack,BeyondTheClouds/nova,paulmathews/nova,fnordahl/nova,badock/nova,luogangyi/bcec-nova,yatinkumbhare/openstack-nova,double12gzh/nova,fajoy/nova,paulmathews/nova,eonpatapon/nova,adelina-t/nova,mahak/nova,gspilio/nova,bigswitch/nova,jeffrey4l/nova,jeffrey4l/nova,citrix-openstack-build/nova,NeCTAR-RC/nova,ewindisch/nova,cloudbau/nova,maoy/zknova,yosshy/nova,mahak/nova,hanlind/nova,devendermishrajio/nova,angdraug/nova,felixma/nova,raildo/nova,barnsnake351/nova,dawnpower/nova,houshengbo/nova_vmware_compute_driver,tudorvio/nova,gooddata/openstack-nova,felixma/nova,rajalokan/nova,josephsuh/extra-specs,paulmathews/nova,thomasem/nova,josephsuh/extra-specs,alaski/nova,russellb/nova,sridevikoushik31/openstack,openstack/nova,kimjaejoong/nova,varunarya10/nova_test_latest,rajalokan/nova,vladikr/nova_drafts,MountainWei/nova,rrader/nova-docker-plugin,savi-dev/nova,rajalokan/nova,leilihh/nova,gooddata/openstack-nova,j-carpentier/nova,angdraug/nova,akash1808/nova_test_latest,petrutlucian94/nova,NoBodyCam/TftpPxeBootBareMetal,qwefi/nova,shail2810/nova,termie/nova-migration-demo,maelnor/nova,usc-isi/nova,belmiromoreira/nova,alexandrucoman/vbox-nova-driver,savi-dev/nova,thomasem/nova,vmturbo/nova,Juniper/nova,apporc/nova,redhat-openstack/nova,plumgrid/plumgrid-nova,savi-dev/nova,Brocade-OpenSource/OpenStack-DNRM-Nova,silenceli/nova,petrutlucian94/nova_dev,russellb/nova,DirectXMan12/nova-hacking,Metaswitch/calico-nova,yrobla/nova,rahulunair/nova,leilihh/novaha,tianweizhang/nova,sridevikoushik31/nova,orbitfp7/nova,isyippee/nova,phenoxim/nova,ntt-sic/nova,salv-orlando/MyRepo,edulramirez/nova,superstack/nova,cloudbase/nova,redhat-openstack/nova,barnsnake351/nova,cyx1231st/nova,sebrandon1/nova,hanlind/nova,sridevikoushik31/nova,viggates/nova,eneabio/nova,CloudServer/nova,yatinkumbhare/openstack-nova,devoid/nova,sacharya/nova,petrutlucian94/nova,TieWei/nova,varunarya10/nova_test_latest,tanglei528/nova,nikesh-mahalka/nova,eneabio/nova,raildo/nova,luogangyi/bcec-nova,JianyuWang/nova,plumgrid/plumgrid-nova,zzicewind/nova,eharney/nova,zhimin711/nova,shootstar/novatest,spring-week-topos/nova-week,akash1808/nova,yrobla/nova,rajalokan/nova,salv-orlando/MyRepo,NewpTone/stacklab-nova,petrutlucian94/nova_dev,ted-gould/nova,bgxavier/nova,Yuriy-Leonov/nova,usc-isi/nova,dims/nova,CEG-FYP-OpenStack/scheduler,mgagne/nova,anotherjesse/nova,citrix-openstack-build/nova,klmitch/nova,tianweizhang/nova,vmturbo/nova,OpenAcademy-OpenStack/nova-scheduler,sridevikoushik31/nova,superstack/nova,psiwczak/openstack,JioCloud/nova_test_latest,zhimin711/nova,leilihh/novaha,virtualopensystems/nova,fajoy/nova,openstack/nova,spring-week-topos/nova-week,dstroppa/openstack-smartos-nova-grizzly,CCI-MOC/nova,dims/nova,cloudbase/nova-virtualbox,cernops/nova,maelnor/nova,devendermishrajio/nova,devendermishrajio/nova_test_latest,noironetworks/nova,whitepages/nova,whitepages/nova,NewpTone/stacklab-nova,shahar-stratoscale/nova,Stavitsky/nova,j-carpentier/nova,mmnelemane/nova,imsplitbit/nova,double12gzh/nova,Yusuke1987/openstack_template,LoHChina/nova,akash1808/nova,rickerc/nova_audit,Francis-Liu/animated-broccoli,eonpatapon/nova,ntt-sic/nova,shahar-stratoscale/nova,zaina/nova,Yuriy-Leonov/nova,eneabio/nova,hanlind/nova,openstack/nova,sebrandon1/nova,watonyweng/nova,termie/nova-migration-demo,TwinkleChawla/nova,Francis-Liu/animated-broccoli,jianghuaw/nova,rickerc/nova_audit,KarimAllah/nova,mikalstill/nova,tudorvio/nova,termie/pupa,apporc/nova,yosshy/nova,KarimAllah/nova,rrader/nova-docker-plugin,sridevikoushik31/openstack,eayunstack/nova,edulramirez/nova,devoid/nova,cernops/nova,tangfeixiong/nova,gooddata/openstack-nova,CiscoSystems/nova,sacharya/nova,affo/nova,noironetworks/nova,zzicewind/nova,jianghuaw/nova,KarimAllah/nova,mmnelemane/nova,russellb/nova,mikalstill/nova,Stavitsky/nova,NewpTone/stacklab-nova,gspilio/nova,berrange/nova,yrobla/nova,maheshp/novatest,eayunstack/nova,termie/pupa,maoy/zknova,cloudbase/nova-virtualbox,usc-isi/extra-specs,BeyondTheClouds/nova,badock/nova,silenceli/nova,adelina-t/nova,cernops/nova,psiwczak/openstack,SUSE-Cloud/nova,NoBodyCam/TftpPxeBootBareMetal,NeCTAR-RC/nova,mahak/nova,takeshineshiro/nova,bigswitch/nova,saleemjaveds/https-github.com-openstack-nova,CCI-MOC/nova,phenoxim/nova,MountainWei/nova,ruslanloman/nova,tangfeixiong/nova,joker946/nova,alexandrucoman/vbox-nova-driver,shootstar/novatest,JioCloud/nova,fnordahl/nova,alaski/nova,aristanetworks/arista-ovs-nova